Synthesized biomaterials have been shown to be useful for engineering tissue regeneration and repair, at least in part because they recapitulate the physical characteristics of the biological tissue environment. For example, synthetic biomaterials have been generated with physical architecture that mimics the extracellular matrix (ECM). These biomaterials have been used as drug carriers and/or tissue engineering scaffolds. However, many of the available synthetic biomaterials are not able to deliver the biochemical cues of the natural ECM. For example, many synthetic biomaterials lack reactive sites for the presentation of desirable biochemical stimuli.